| Summary: | Previous research has documented a tight positive relationship between vegetation activity and growing season air temperature in China’s temperate zone (TC). However, this relationship may change over time following alternations in other environmental factors. Using the linear regression analysis and the moving windows based on partial correlation analysis method, the temporal variations of responses of vegetation NDVI to rising air temperature during 1982–2015 in the TC were examined. The results showed that the interannual partial correlation between NDVI and air temperature (R<sub>NDVI−T</sub>, include R<sub>NDVI−Tmean</sub>, R<sub>NDVI−Tmax</sub>, and R<sub>NDVI−Tmin</sub>, represents the partial correlation between NDVI and T<sub>mean</sub>, T<sub>max</sub>, and T<sub>min</sub>, respectively) for the growing season (GS) in a 17−year moving window showed a significant decreasing trend during the last 34 years, mainly due to decreasing R<sub>NDVI−T</sub> in summer and autumn. The area with a significant decrease of R<sub>NDVI−Tmean</sub>, R<sub>NDVI−Tmax</sub>, and R<sub>NDVI−Tmin</sub> for the GS approximately accounted for 52.36%, 45.63%, and 49.98% of the TC, respectively. For the seasonal patterns of R<sub>NDVI−T</sub>, the regions with a significant downward trend in all seasons were higher than those with a significant upward trend. We also found a more significant and accelerating decrease of R<sub>NDVI−T</sub> for warm years compared to cold years, implying a decoupling or even a reverse correlation between NDVI and air temperature with continuous climate warming over the TC. Overall, our study provided evidence that the impact of T<sub>mean</sub>, T<sub>max</sub>, and T<sub>min</sub> on vegetation activities exhibited a weakening trend and cautioned using results from interannual time scales to constrain the decadal response of vegetation growth to future global warming.
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